575 research outputs found
Evaluating abiotic influences on soil salinity of inland managed wetlands and agricultural fields in a semi-arid environment
Agriculture and moist-soil management are important management techniques used on wildlife refuges to provide adequate energy for migrant and wintering waterbirds. However, in arid systems, the presence and accumulation of soluble salts throughout the soil profile can limit total biomass production of wetland plants and agronomic crops and thus jeopardize meeting waterbird energy needs. It is unknown how moist-soil management and traditional agriculture practices influence the accumulation and distribution of soluble salts of soil profiles. In this study of an arid wetland ecosystem, I determine: 1) the effect of long-term, distinct surface hydrologic regimes associated with moist-soil management and agricultural production on salt accumulation; and 2) the specific effects of rototillage and irrigation frequency on salinity concentrations and plant biomass in moist-soil impoundments. My study was conducted at Bosque del Apache National Wildlife Refuge near San Antonio, New Mexico. In May 2012, prior to the growing season, I collected one meter deep soil cores from both moist-soil impoundments and agricultural fields; cores were analyzed in 10 cm segments for soluble salt concentrations. I implemented a split-plot experiment to evaluate salinity concentrations in moist-soil impoundments between rototilled and no-till soils under a 9 and 14 day irrigation frequency. Soil salinity was measured in May and August of 2011 and 2012 and plant biomass in August. My findings suggest that agricultural fields contain significantly higher concentrations of soluble salts in deeper portions of the profile. This may be attributed to the lack of leaching afforded by summer agricultural irrigations as little connectivity to the groundwater and groundwater salinity was detected during groundwater monitoring. In contrast, periodic flooding in winter and summer flood irrigations in moist-soil impoundments may serve as leaching events and created a more dynamic groundwater hydrograph. This seasonal wetland hydroperiod may facilitate lower soil profile salinities but further research is needed to evaluate its successful use in agriculture fields to lower soil salinities. Few differences in soil salinity were detected between tillage and irrigation treatments within moist-soil impoundments. However plant above ground biomass of annual wetland grasses was greater in rototilled soils. This is most likely attributed to the effects of physical disturbance that stimulates germination rather than differences in soil salinity, however greater aboveground biomass does not necessarily equate to higher seed or tuber production
Multi-physics ensemble snow modelling in the western Himalaya
Combining multiple data sources with multi-physics simulation frameworks offers new potential to extend snow model inter-comparison efforts to the Himalaya. As such, this study evaluates the sensitivity of simulated regional snow cover and runoff dynamics to different snowpack process representations. The evaluation is based on a spatially distributed version of the Factorial Snowpack Model (FSM) set up for the Astore catchment in the upper Indus basin. The FSM multi-physics model was driven by climate fields from the High Asia Refined Analysis (HAR) dynamical downscaling product. Ensemble performance was evaluated primarily using MODIS remote sensing of snow-covered area, albedo and land surface temperature. In line with previous snow model inter-comparisons, no single FSM configuration performs best in all of the years simulated. However, the results demonstrate that performance variation in this case is at least partly related to inaccuracies in the sequencing of inter-annual variation in HAR climate inputs, not just FSM model limitations. Ensemble spread is dominated by interactions between parameterisations of albedo, snowpack hydrology and atmospheric stability effects on turbulent heat fluxes. The resulting ensemble structure is similar in different years, which leads to systematic divergence in ablation and mass balance at high elevations. While ensemble spread and errors are notably lower when viewed as anomalies, FSM configurations show important differences in their absolute sensitivity to climate variation. Comparison with observations suggests that a subset of the ensemble should be retained for climate change projections, namely those members including prognostic albedo and liquid water retention, refreezing and drainage processes
Twitter: More than Tweets for Undergraduate Student Researchers
During the COVID-19 pandemic, biology educators were forced to think of ways to communicate with their students, engaging them in science and with the scientific community. For educators using course-based undergraduate research experiences (CUREs), the challenge to have students perform real science, analyze their work, and present their results to a larger scientific audience was difficult as the world moved online. Many instructors were able to adapt CUREs utilizing online data analysis and virtual meeting software for class discussions and synchronous learning. However, interaction with the larger scientific community, an integral component of making science relevant for students and allowing them to network with other young scientists and experts in their fields, was still missing. Even before COVID-19, a subset of students would travel to regional or national meetings to present their work, but most did not have these opportunities. With over 300 million active users, Twitter provided a unique platform for students to present their work to a large and varied audience. The Cell Biology Education Consortium hosted an innovative scientific poster session entirely on Twitter to engage undergraduate researchers with one another and with the much broader community. The format for posting on this popular social media platform challenged students to simplify their science and make their points using only a few words and slides. Nineteen institutions and over one hundred students participated in this event. Even though these practices emerged as a necessity during the COVID-19 pandemic, the Twitter presentation strategy shared in this paper can be used widely
Combinations of idelalisib with rituximab and/or bendamustine in patients with recurrent indolent non-Hodgkin lymphoma
Key Points
Combining phosphatidylinositol-3-kinase δ inhibition with rituximab, bendamustine, or both is feasible and active in relapsed iNHL. The safety of novel combinations should be proven in phase 3 trials before adoption in clinical practice.</jats:p
Durable Response After Tisagenlecleucel in Adults With Relapsed/Refractory Follicular Lymphoma: ELARA Trial Update
Tisagenlecleucel is approved for adults with relapsed/refractory (r/r) follicular lymphoma (FL) in the ≥3rd-line setting. The primary analysis (median follow-up: 17 months) of the Phase II ELARA trial (ClinicalTrials.gov identifier: NCT03568461) reported high response rates and excellent safety profile in extensively pretreated patients with r/r FL. Here we report longer-term efficacy, safety, pharmacokinetic, and exploratory biomarker analyses after a median follow-up of 29 months. As of March 29, 2022, 97 patients with r/r FL (grades 1-3A) after ≥2 lines of therapy or who relapsed after autologous stem cell transplant received tisagenlecleucel infusion (0.6-6×108 CAR+ viable T cells). Bridging chemotherapy was allowed. Baseline clinical factors, tumor microenvironment (TME), blood soluble factors, and circulating blood cells were correlated with clinical response. Cellular kinetics were assessed by quantitative polymerase chain reaction. Median progression-free survival (PFS), duration of response (DOR), and overall survival (OS) were not reached after 29 months median follow-up (IQR, 22.2-37.7). Estimated 24-month PFS, DOR, and OS rates in all patients were 57.4% (95% CI, 46.2-67), 66.4% (95% CI, 54.3-76), and 87.7% (95% CI, 78.3-93.2). Complete response rate and overall response rate were 68.1% (95% CI, 57.7-77.3) and 86.2% (95% CI, 77.5-92.4), respectively. No new safety signals or treatment-related deaths were reported. Low levels of tumor-infiltrating LAG3+CD3+ exhausted T-cells and higher baseline levels of naïve CD8+ T-cells were associated with improved outcomes. Tisagenlecleucel continued to demonstrate highly durable efficacy and a favorable safety profile in this extended follow-up of 29 months in patients with r/r FL enrolled in ELARA
LIS1 Regulates Osteoclast Formation and Function through Its Interactions with Dynein/Dynactin and Plekhm1
Microtubule organization and lysosomal secretion are both critical for the activation and function of osteoclasts, highly specialized polykaryons that are responsible for bone resorption and skeletal homeostasis. Here, we have identified a novel interaction between microtubule regulator LIS1 and Plekhm1, a lysosome-associated protein implicated in osteoclast secretion. Decreasing LIS1 expression by shRNA dramatically attenuated osteoclast formation and function, as shown by a decreased number of mature osteoclasts differentiated from bone marrow macrophages, diminished resorption pits formation, and reduced level of CTx-I, a bone resorption marker. The ablated osteoclast formation in LIS1-depleted macrophages was associated with a significant decrease in macrophage proliferation, osteoclast survival and differentiation, which were caused by reduced activation of ERK and AKT by M-CSF, prolonged RANKL-induced JNK activation and declined expression of NFAT-c1, a master transcription factor of osteoclast differentiation. Consistent with its critical role in microtubule organization and dynein function in other cell types, we found that LIS1 binds to and colocalizes with dynein in osteoclasts. Loss of LIS1 led to disorganized microtubules and aberrant dynein function. More importantly, the depletion of LIS1 in osteoclasts inhibited the secretion of Cathepsin K, a crucial lysosomal hydrolase for bone degradation, and reduced the motility of osteoclast precursors. These results indicate that LIS1 is a previously unrecognized regulator of osteoclast formation, microtubule organization, and lysosomal secretion by virtue of its ability to modulate dynein function and Plekhm1
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